MAYS LANDING — An Atlantic City man was sentenced to 15 years in state prison for robbing a convenience store at gunpoint, authorities said.

Matthew Bumpers, 24, was sentenced Monday for robbing the 24/7 Food Mart on Pacific Avenue in Atlantic City a year ago, said Jim McClain, the acting Atlantic County Prosecutor.

Bumpers was caught immediately after the Feb. 12, 2013 robbery – but his accomplice was never found or identified, authorities said.

Bumpers and the accomplice entered the convenience store, assaulted the cashier, and demanded money at gunpoint, McClain said. The pair took $200, cigarettes and a cell phone – and then damaged the store’s phone landline to prevent the cashier from calling the police, the prosecutor said.

A worker at the company’s other store one block away witnessed the robbery on the joint-surveillance system for the stores, authorities said. The co-workers ran to the scene and chased both of the robbers from the store, McClain said.

The employee chased Bumpers onto a jitney, then got in his car and followed it, while calling 911 to report the robbery, McClain said.

An Atlantic City police officer was flagged down by the employee, and Bumpers was chased and found under a nearby deck, McClain said.

Bumper was convicted by a jury after 30 minutes of deliberation on counts of first-degree armed robbery, conspiracy to commit armed robbery, aggravated assault, and weapons offenses.

Bumpers will have to serve 12 years and 9 months of his sentence before becoming eligible for parole, under the terms of the No Early Release Act, McClain added.